Background Frequently, clinicians have difficulty interpreting CT scans and MRI's
done on patients with cancer, particularly after surgery or radiation therapy. Positron emission tomography (PET) is an imaging technique that measures glucose metabolism in cells. There is evidence that tumor cells have increased uptake and metabolism of these sugar molecules, as compared to non-malignant cells. Fluorodeoxyglucose (FDG)is the radioactive tracer used in this technique. Standard uptake values (SUV) measure the intensity of tracer identified on the PET study. It is generally accepted that higher SUV are more likey to represent malignancy as opposed to scaring or inflamation.

Materials and
Methods

This was a prospective study evaluating PET as a prognosticator in patients with non-small cell lung cancer who received chemotherapy or chemoirradiation.

88 patients were evaluated, most had stage III disease.

Most got chemoirradiation.

Most had good performance status.

The majority had squamous cell histology.

PET responses were assessed by comparing initial and post-treatment scans.